Cake soap has been used time immemorial as a product for body cleanliness and personal hygiene and over the years many improvements have been made to such cake soap products to enable one to more effectively and efficiently clean the body or skin of the user. Such cake soap products were primarily produced from saponified animal and vegetable fats and oils.
Originally, shampoos for the hair or scalp were made from soap or mixtures of soaps. However, such shampoos were not readily accepted and used for a number of reasons including the highly undesirable poor lathering and their tendency to form a lime soap deposit, residue or film on the hair or scalp, particularly in hard-water areas, by way of the formation of insoluble calcium and magnesium salts due to the presence of carboxylic groups linked to long-chain hydrocarbons. For the most part, use of such cake soaps as shampoos has been abandoned except in "emergency" type situations where the user is without a shampoo and cleansing of the hair is an "immediate necessity".
Due to the aforesaid drawbacks, special shampoo products for the hair and scalp were formulated. These shampoo products have been in the form of clear or opaque liquids, lotions, pastes, gels, aerosols and dry absorbent powder products. For the most part, these shampoos are now produced from synthetic detergents. The shampoo products have been produced in the aforesaid forms but have not been available commercially in acceptable form in solid bar or cake form. Cake or bar soaps which have been available for use in cleansing the skin or body have not been useful as shampoos, particularly as shampoos having hair conditioning properties, due to the undesirable residue or deposit left on the hair or scalp when such bar soap is attempted to be used as a shampoo medium.
It is therefore highly desirable to provide a composition that can be formed into a solid bar or cake and which is useful both as a shampoo for the hair or scalp and also as a cleansing soap for the skin or body. It is also desirable that such a composition be provided which will remove surface grease, dirt, skin debris and natural skin secretions from the hair shaft or scalp without leaving a soap residue on the hair or scalp and yet functions effectively as a skin or body cleansing soap with sufficient lathering and cleansing action for both body and hair. It is a further object of this invention to provide such a solid shampoo and soap product which contains hair conditioning agents.